Patients with Charcot neuropathy may experience swelling, and joint subluxation (dislocation). Eventually, the mal-positioning of the joints can result in a bony prominence beneath the foot. Patients with neuropathy may not experience pain, and may continue to walk and bear weight on the affected foot. If left untreated, ulceration and infection may result. Treatment goals include allowing the ulcers to heal, creating a plantagrade foot, and preventing infection.
“Meary's angle” is one measure of the deformity of the foot. Meary's angle is the angle between the central longitudinal axis of the talus and the central longitudinal axis of the first metatarsal, as viewed in a vertical (parasagittal) plane. In a normal foot, Meary's angle is 0 degrees. In the case of a Charcot foot, Meary's angle can reach 15-30 degrees or more.
To eliminate the bony prominence and restore the arch in patients with severe Charcot deformity affecting multiple foot joints, surgeons have performed a biplanar wedge osteotomy. In this procedure, the surgeon removes a biplanar wedge of bone from the plantar side of the foot. By rejoining the remaining bones, the surgeon is able to restore the foot into a stable plantagrade foot that can fit in a shoe and can support activity with proper bracing. Thus, the surgeon tries to reduce Meary's angle to approximately zero (i.e., between zero and four degrees).